General Model to Represent Multiple Wetland and Lake Stage-Storage Behavior

Quantifying wetland and lake storage is crucial for developing accurate hydrologic models, especially in regional or large watershed applications with potentially hundreds or thousands of wetlands where detailed survey data are unavailable. This paper evaluates an analytical method that uses a volume-depth (V-h) power-function model and a single general shape parameter to predict the storage behavior of multiple wetlands and lakes. This study (1) developed a general shape parameter (i.e., general V-h model) that defines the stage-storage relationships of wetlands and lakes from a diverse and extensive development data set; (2) evaluated the errors associated with storage or stage predictions based on the V-h model; and (3) tested the general V-h model performance on an independent validation data set. The study findings were as follows: (1) General wetland and lake shape parameters were shown to approximately represent stage-storage relationships of each wetland and lake group in this study; (2) the diversity of the wetland topography associated with an individual wetland group was an important factor that affected the general shape parameter effectiveness; and (3) general V-h models were able to predict the storage characteristics of the validation data set with average relative errors of 43% for volume and 14% for stage. Additionally, the analysis quantified the potential error introduced into the model when using this technique. This analysis demonstrates that a general shape parameter coupled with the V-h power-function model could be used to represent wetland and lake stage-storage behavior where detailed bathymetry surveys are unavailable or sparse, or as a calibration parameter in a hydrologic model.